package Stringdemo;
import java.util.StringJoiner;
public class Stringjoiner {
    public static void main(String[] args){
        StringJoiner sj = new StringJoiner(",","[","]");
        sj.add("aaa").add("bbb").add("ccc");
        String str = sj.toString();
        System.out.println(sj);
    }
}
